Natural Order - The Magic of 150

Tribe Size

Your brain is hard wired to pay attention to about
150 people. Try to have a relationship with any more than that, and
your life will turn to pure crap. Just ask the Military, Gore-Tex, or
Krippendorf's tribe. They'll all tell you the same thing. One fifty is
the way to go. They've known for hundreds of years that people work
best in groups of 150 or less. Now it's your
turn.
The human cortex, responsible for complex thought and reasoning, is
overgrown in humans when compared to other mammals. Scientists have
argued for years about why this is the case.

One theory holds that our brains evolved because our primate ancestors
began to gather food in more complex ways. They began eating fruit
instead of grasses and leaves. This involved traveling long distances
to find food, and required each species to maintain a complex mental
map in order to keep track of fruit trees. More brainpower might have
been needed to determine if a fruit was ripe, or to discern proper
methods for peeling fruit or cracking nuts.

The problem with this theory is that if one tries to match brain size
with the eating habits of primates, it doesn't work. Some small-brained
monkeys are eating fruit and maintaining complex maps and some larger
brained primates are eating leaves.

What does work, apparently, is group size. If one examines any species
of primate, the larger their neocortex, the larger the average size of
the group they live with.

Anthropologist Robin Dunbar has done some of the most interesting
research in this area. Dunbar's argument is that as brains evolve, they
become larger in order to handle the unique complexities of larger
social groups. Humans socialize the largest social groups because we
have the largest cortex. Dunbar has developed an equation, which works
for most primates, in which he plugs in what he calls the neocortex
ratio of a particular species - the size of the neocortex relative to
the size of the brain - and the equation gives us the maximum expected
group size for each species. For humans, the max group size is 147.8,
or about 150. This figure seems to represent the maximum amount of
people that we can have a real social relationship with - knowing who
another human is and how they relate to us.

Dunbar has gone through anthropological literature and found that the
number 150 pops up over and over again. For example, he looked at 21
different hunger-gatherer societies around the world and found that the
average number of people in each village was 148.4.

The same pattern holds true for military organization. Over the years,
through trial and error, military planners have arrived at a rule of
thumb for the size of a functional fighting unit - 200 men. They have
realized that it is quite difficult to make any larger a group than
this to function as a unit without complicated hierarchies and rules
and regulations and formal measures to insure loyalty and unity within
the group. With a group of 150 or so, formalities are not necessary.
Behavior can be controlled on the basis of personal loyalties and
direct man-to-man contacts. With larger groups, this seems impossible.

Further is the religious group known as the Hutterites, who for
hundreds of years, through trial and error, have realized that the
maximum size for a colony should be, low and behold, 150 people.
They've been following this rule for centuries. Every time a colony
approaches this number, the colony is divided into two separate
colonies. They have found that once a group becomes larger than that,
"people become strangers to one another." At 150, the Hutterites
believe, something happens that somehow changes the community seemingly
overnight. At 150 the colony with spontaneously begin dividing into
smaller "clans." When this happens a new colony is formed.

Another good example of our hard wired social limits is Gore
Associates, a privately held multimillion-dollar company responsible
for creating Gore-Tex fabric and all sorts of other high tech computer
cables, filter bags, semiconductors, pharmaceutical, and medical
products. What is most unique about this company is that each company
plant is no larger than 150. When constructing a plant, they put 150
spaces in the parking lot, and when people start parking on the grass,
they know it's time for another plant. Each plant works as a group.
There are no bosses. No titles. Salaries are determined collectively.
No organization charts, no budgets, no elaborate strategic plans.
Wilbert Gore - the late founder of the company, found through trial and
error that 150 employees per plant was most ideal. "We found again and
again that things get clumsy at a hundred and fifty," he told an
interviewer some years ago.

Take a lesson from this. If you are engaged in a large enterprise or
are planning to work for one, realize that large groups rapidly reduce
the efficiency of an operation. If each department is separated,
especially if there are hundreds or thousands of people involved,
complex systems of organizations will be required to keep everyone in
check. Peer pressure is much more powerful than the somehow vague
concept of a boss or punishment. People will work only hard enough not
to get fired in a very large group, but will live up to the
expectations of their peers in smaller groups where they have a
personal relationship with each of their co-workers. Of course, a small
group size is not by any means a guarantee of success. Small
enterprises fail all the time. It's just a concept -- an idea to keep
in the back of your mind as you vegetate in that basement cubicle.

For more information:
R.I.M Dunbar, "Neocortex size as a constraint on group size in
primates," Journal of Human Evolution (1992), vol. 20, pp. 469-493.